Structural, functional and biological insights into the role of Mycobacterium tuberculosis VapBC11 toxin-antitoxin system: targeting a tRNase to tackle mycobacterial adaptation.
Structural, functional and biological insights into the role of Mycobacterium tuberculosis VapBC11 toxin-antitoxin system: targeting a tRNase to tackle mycobacterial adaptation.
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DOI：
10.1093/nar/gky924
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发表时间：
2018-11-30
影响因子：
14.9
通讯作者：
Thakur KG
中科院分区：
文献类型：
--
作者：
Deep A;Tiwari P;Agarwal S;Kaundal S;Kidwai S;Singh R;Thakur KG
毒素-抗毒素（TA）系统参与原核生物的多种生理过程，但其在结核分枝杆菌（Mtb）毒力和体内应激适应中的确切作用尚未得到广泛研究。在这里，我们证明了VapBC11 TA模块对于Mtb在豚鼠中建立感染是必不可少的。rna测序显示，过表达VapC11毒素会导致代谢减慢，这表明调节生长速度是体内生存的重要策略。有趣的是，VapC11的过表达导致染色体TA基因上调，表明TA系统之间存在高度协调的串扰。在本研究中，我们还以1.67 Å分辨率展示了VapBC11异聚络合物的晶体结构。结合动力学研究表明，毒素-底物和毒素-抗毒素相互作用的结合亲和力是相似的。我们采用结构研究、分子对接、突变分析和体外核糖核酸酶测定相结合的方法来加深我们对VapC11毒素识别底物模式的理解。此外，我们还设计了基于肽的抑制剂来靶向VapC11核糖核酸酶活性。综上所述，我们提出以结构为导向设计体内必需核糖核酸酶抑制剂可能是加速细胞内结核分枝杆菌清除的新策略。
Toxin–antitoxin (TA) systems are involved in diverse physiological processes in prokaryotes, but their exact role in Mycobacterium tuberculosis (Mtb) virulence and in vivo stress adaptation has not been extensively studied. Here, we demonstrate that the VapBC11 TA module is essential for Mtb to establish infection in guinea pigs. RNA-sequencing revealed that overexpression of VapC11 toxin results in metabolic slowdown, suggesting that modulation of the growth rate is an essential strategy for in vivo survival. Interestingly, overexpression of VapC11 resulted in the upregulation of chromosomal TA genes, suggesting the existence of highly coordinated crosstalk among TA systems. In this study, we also present the crystal structure of the VapBC11 heterooctameric complex at 1.67 Å resolution. Binding kinetic studies suggest that the binding affinities of toxin–substrate and toxin–antitoxin interactions are comparable. We used a combination of structural studies, molecular docking, mutational analysis and in vitro ribonuclease assays to enhance our understanding of the mode of substrate recognition by the VapC11 toxin. Furthermore, we have also designed peptide-based inhibitors to target VapC11 ribonuclease activity. Taken together, we propose that the structure-guided design of inhibitors against in vivo essential ribonucleases might be a novel strategy to hasten clearance of intracellular Mtb.
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影响因子：
6.4
作者：
Fontan, Patricia A.;Aris, Virginie;Smith, Issar
通讯作者：
Smith, Issar
DOI：
10.1007/978-3-319-46503-6_14
发表时间：
2017-01-01
期刊：
MACROMOLECULAR PROTEIN COMPLEXES: STRUCTURE AND FUNCTION
影响因子：
--
作者：
Bendtsen, Kirstine L.;Brodersen, Ditlev E.
通讯作者：
Brodersen, Ditlev E.
影响因子：
3
作者：
Das, Uddipan;Pogenberg, Vivian;Srinivasan, Alagiri
通讯作者：
Srinivasan, Alagiri
影响因子：
11.3
作者：
Gengenbacher M;Kaufmann SH
通讯作者：
Kaufmann SH
DOI：
10.1107/s0907444909052925
发表时间：
2010-02
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Adams PD;Afonine PV;Bunkóczi G;Chen VB;Davis IW;Echols N;Headd JJ;Hung LW;Kapral GJ;Grosse-Kunstleve RW;McCoy AJ;Moriarty NW;Oeffner R;Read RJ;Richardson DC;Richardson JS;Terwilliger TC;Zwart PH
通讯作者：
Zwart PH